your timing sucks they were up for over a month with insta-ship..... chances are they will be back pretty soon, i couldn't see you having to wait 6 months or more, that said i do think it may be longer than normal with them trying to push the 58x jubilee or whatever the number is, they are within $50 of each other and having the hd6xx running at the same time kinda makes the jubilees useless, so i really wouldn't expect to see both of them running side by side again and depending on which one they decide to run will put the other one further out.... so yeah depending on what happens i could be wrong about with the 6 month time frame, could actually be a bit longer...from my reading around it kinda sounded like they ran the hd6xx's a few times a year....seeing with how long they ran recently i would guess it will be a minute....
just a bunch of speculation on my part though..... you really should have gotten in on them when they were up and shipping for the last month and a half....
that said, i'm in for a second pair when they go up again, i have the 598's and the hd6xx's, the hd6xx's are by far the better headphone and out of the collection they are some of my fav's I'll be buying a second pair for when the 1st pair enviably get ruined.

Thanks for the reply man! Well i really wanted to pick them up this time. However when i was putting in my order I realized that Massdrop does not deliver this particular drop to my country. So Im gonna have to have someone pick them up for me in the US and mail them to me. Hope they drop again soon,